The present invention relates to a disposable body warmer, and more particularly to a disposable body warmer which has a good rising (i.e. the rising in temperature is fast) and can maintain a predetermined high temperature condition for a long time.
A disposable body warmer is based on the fact if air is supplied to a mixture comprising metal powder available with relatively low cost such as iron powder and assistance such as water, wood flour and sodium chloride contained in an air-permeable bag, it generates heat. The disposable body warmer is easy to carry and can be easily used by merely openning an outer bag, so that it occupies a major proportion of body warmers in these days.
In such disposable body warmers, sodium chloride has generally been used as a catalyst to promote exothermic reaction. However, the body warmer with sodium chloride as a catalyst does not always bring satisfaction with regard to rising rate in temperature, duration and warmness, because sodium chloride is unevenly oxidized.
In view of the above-mentioned circumstance, it is an object of the present invention to provide a disposable body warmer with which the conventional problem is solved. That is, it is an object of the present invention to provide a disposable body warmer with which time required to reach a predetermined temperature from just after beginning of exothermic reaction is short, and duration at the predetermined temperature is long.